Evidence for low density holes in Jupiter’s ionosphere

Abstract

Intense electromagnetic impulses induced by Jupiter’s lightning have been recognised to produce both low-frequency dispersed whistler emissions and non-dispersed radio pulses. Here we report the discovery of electromagnetic pulses associated with Jovian lightning. Detected by the Juno Waves instrument during its polar perijove passes, the dispersed millisecond pulses called Jupiter dispersed pulses (JDPs) provide evidence of low density holes in Jupiter’s ionosphere. 445 of these JDP emissions have been observed in snapshots of electric field waveforms. Assuming that the maximum delay occurs in the vicinity of the free space ordinary mode cutoff frequency, we estimate the characteristic plasma densities (5.1 to 250\u2009cm−3) and lengths (0.6\u2009km to 1.3\u2009×\u2009105\u2009km) of plasma irregularities along the line of propagation from lightning to Juno. These irregularities show a direct link to low plasma density holes with ≤250\u2009cm−3 in the nightside ionosphere.Intense electromagnetic impulses induced by Jupiter’s lightning can produce both low-frequency dispersed whistler emissions and non-dispersed radio pulses. Here, the authors show Jupiter dispersed pulses associated with Jovian lightning that are evidence of low density holes in Jupiter’s ionosphere.